<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      function getWeekDay(d) {
        const ws = {
          1: '1',
          2: '2',
          3: '3',
          4: '4',
          5: '5',
          6: '6',
          0: '7',
        };
        // console.log(ws[d.getDay()]);
        return ws[d.getDay()];
      }
      const r = getWeekDay(new Date(2012, 1, 20, 3, 12));
      console.log(r);
    </script>
  </body>
</html>
